(a) Field of the Invention
The present invention relates to an oil supply circuit for a cylinder deactivation system. More particularly, the present invention relates to an oil supply circuit for a cylinder deactivation system having a simple structure and capable of being installed at a cylinder head without needing additional extraneous elements by forming an oil line in a cam shaft of a hollow space.
(b) Description of the Related Art
A cylinder deactivation system is a system that stops unnecessary cylinders according to a driving condition. The cylinder deactivation system can improve fuel consumption by stopping the unnecessary cylinders.
According to the cylinder deactivation system, operations of intake and exhaust cams are controlled by supplying high pressure oil or low pressure oil to tappets that control openings of intake and exhaust valves according to driving conditions. That is, the cams rotate but the valves do not operate when the high pressure oil is supplied to the tappets. On the other hand, the cams rotate and the valves also operate when the low pressure oil is supplied to the tappets.
According to a conventional cylinder deactivation system, an oil supply circuit for supplying the high pressure oil and the low pressure oil to the tappets may be complex and may need additional extraneous elements so as to install the oil supply circuit at a cylinder head.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.